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Chinese Journal of Chemical Engineering 2024年第4期68卷 16-26页

作者： Zhi Hu Jiahong Wang Tongtong sun School of Environmental Science and Engineering Shaanxi University of Science&TechnologyXi'an 710021China Shaanxi Key Laboratory of Green Preparation and Functionalization of Inorganic Materials Xi'an 710021China

A novel tetraethylenepentamine(TEPA) functionalized magnetic mesoporous silica adsorbent(FNMs/TEPA) was prepared for the adsorption of Cr(Ⅲ)-ethylenediaminetetraacetic acid(EDTA)from wastewater. The characterization of the prepared adsorbent certified that TEPA was modified onto the magnetic mesoporous silicon(FNMs), while FNMs/TEPA maintained the ordered mesoporous and pristine magnetic properties. The batch adsorption experiments demonstrated that TEPA significantly enhanced the removal capacity of the adsorbent for Cr(Ⅲ)-EDTA. FNMs/TEPA exhibited an excellent adsorption property(13.84 mg·g-1) at p H 4.0. Even in the presence of high concentrations of coexisting ions and organic acids, the adsorption performance of FNMs/TEPA was stable. Experimental characterization and DFT demonstrated that the adsorption of Cr(Ⅲ)-EDTA was ascribed to the electrostatic interaction, hydrogen bonding, and complexation between Cr(Ⅲ)-EDTA and amino groups on the adsorbent surface. The analysis of the independent gradient model(IGM) shows that electrostatic interaction is the main mode of action in the adsorption process. Moreover, FNMs/TEPA demonstrated remarkable reusability in three regeneration cycles. These findings indicated that FNMs/TEPA possessed excellent application prospects in the disposal of wastewater containing Cr(Ⅲ)-EDTA.

关键词： TEPA functionalized magnetic mesoporous silicon Adsorption Cr(III)-EDTA Density functional theory calculations

Estimates of net primary productivity and actual evapotranspiration over the Tibetan Plateau from the Community Land Model version 4.5 with four atmospheric forcing datasets

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Journal of Plant Ecology 2024年第4期17卷 70-89页

作者： Shan Lin Kewei Huang Xiangyang sun Chunlin Song Juying sun Shouqin sun Genxu Wang Zhaoyong Hu State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China Hubei Key Laboratory of Basin Water Security Changjiang SurveyPlanningDesign and Research Co.Ltd.Wuhan 430010China Research Unit Forest Dynamics Swiss Federal Research Institute for ForestSnow and Landscape Research WSLBirmensdorf 8903Switzerland

The accuracy of the simulation of carbon and water processes largely relies on the selection of atmospheric forcing datasets when driving land surface models(LSM).Particularly in high-altitude regions,choosing appropriate atmospheric forcing datasets can effectively reduce uncertainties in the LSM ***,this study conducted four offline LSM simulations over the Tibetan Plateau(TP)using the Community Land Model version 4.5(CLM4.5)driven by four state-of-the-art atmospheric forcing *** performances of CRUNCEP(CLM4.5 model default)and three other reanalysis-based atmospheric forcing datasets(***,GSWP3 and WFDEI)in simulating the net primary productivity(NPP)and actual evapotranspiration(ET)were evaluated based on in situ and gridded reference *** with in situ observations,simulated results exhibited determination coefficients(R2)ranging from 0.58 to 0.84 and 0.59 to 0.87 for observed NPP and ET,respectively,among which GSWP3 and ITPCAS showed superior *** the plateau level,CRUNCEP-based simulations displayed the largest bias compared with the reference NPP and ***3-based simulations demonstrated the best performance when comprehensively considering both the magnitudes and change trends of TP-averaged NPP and *** simulated ET increase over the TP during 1982-2010 based on ITPCAS was significantly greater than in the other three simulations and reference ET,suggesting that ITPCAS may not be appropriate for studying long-term ET changes over the *** results suggest that GSWP3 is recommended for driving CLM4.5 in conducting long-term carbon and water processes simulations over the *** study contributes to enhancing the accuracy of LSM in water-carbon simulations over alpine regions.

关键词： land surface model carbon cycle water cycle high altitude Community Land Model version 4.5

Adaptive Dead-Time Modulation Scheme for Bidirectional LLC Resonant Converter in Energy Router

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1710-1721页

作者： Chenghao sun Qiuye sun Rui Wang Yuyang Li Dazhong Ma College of Information Science and Engineering Northeastern UniversityShenyang 110819China

Although the dead-time optimization design of resonant converters has been widely researched,classical design methods focus more on achieving zero-voltage switching(ZVS)*** body diode loss is always ignored,which results in low-efficiency of the converter,especially,in energy router(ER).To deal with this problem,this paper proposes an adaptive deadtime modulation scheme for bidirectional LLC resonant converters in ***,the power loss of the MOSFET is analyzed based on the ***,a novel dead-time optimization modulation principle is *** can eliminate the body diode loss of MOSFET compared with existing *** on the optimization modulation principle,this paper proposes an adaptive dead-time modulation *** this end,the converter adopting the scheme no longer needs to calculate dead-time,which simplifies the parameter design ***,this scheme enables dead-time to dynamically change with working conditions according to the dead-time optimization modulation *** these effects,the ZVS operation is achieved,and the body diode loss of MOSFET is also ***,a digital implementation method is designed to make the proposed modulation scheme have fast-transient ***,experimental results show that the proposed dead-time modulation scheme enables converters to achieve ZVS operation in all working conditions,and has higher efficiency than classical dead-time design methods.

关键词： Adaptive modulation bidirectional LLC body diode loss dead-time energy router ZVS

A Methodology for Assessing Axial Compressor Stability with Inlet Temperature Ramp Distortion

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Journal of Thermal Science 2024年第3期33卷 856-871页

作者： sun Dakun GU Benhao NING Fangfei FANG Yibo DONG Xu XU Dengke sun Xiaofeng School of Energy and Power Engineering Beihang UniversityBeijing102206China Research Institute of Aero-engine Beihang UniversityBeijing102206China

Based on a small perturbation stability model for periodic flow,the effects of inlet total temperature ramp distortion on the axial compressor are investigated and the compressor stability is quantitatively *** the beginning,a small perturbation stability model for the periodic flow in compressors is proposed,referring to the governing equations of the Harmonic Balance *** stability model is validated on a single-stage low-speed compressor TA36 with uniform inlet ***,the unsteady flow of TA36 with different inlet total temperature ramps and constant back pressure is simulated based on the Harmonic Balance *** on these simulations,the compressor stability is analyzed using the proposed small perturbation ***,the Dynamic Mode Decomposition method is employed to accurately extract pressure *** two parameters of the temperature ramp,ramp rate and Strouhal number,are discussed in this *** results indicate the occurrence and extension of hysteresis loops in the rows,and a decrease in compressor stability with increasing ramp *** performance is divided into two phases,stable and limit,based on the ramp ***,the model predictions suggest that a decrease in period length and an increase in Strouhal number lead to improved compressor *** DMD results imply that for compressors with inlet temperature ramp distortion,the increase of high-order modes and oscillations at the rotor tip is always the signal of decreasing stability.

关键词： axial compressor stability small perturbation model inlet temperature ramp distortion harmonic balance method dynamic mode decomposition method

Solubility of iron(Ⅲ) and nickel(Ⅱ) acetylacetonates in supercritical carbon dioxide

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Chinese Journal of Chemical Engineering 2024年第1期65卷 29-34页

作者： Haixin sun Jianlei Qi Jianfei sun Lin Li Kunpeng Yu Jintao Wu Jianzhong Yin State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024China College of Chemical Engineering Inner Mongolia University of TechnologyHohhot 010051China

As a common precursor for supercritical CO_(2)(scCO_(2))deposition techniques,solubility data of organometallic complexes in scCO_(2)is crucial for the preparation of ***,metal acetylacetonates have shown great potential for the preparation of single-atom catalytic *** this study,the solubilities of iron(Ⅲ)acetylacetonate(Fe(acac)3)and nickel(Ⅱ)acetylacetonate(Ni(acac)2)were measured at the temperature from 313.15 to 333.15 K and in the pressure range of 9.5–25.2 MPa to accumulate new solubility *** was measured using a static weight loss *** semi-empirical models proposed by Chrastil and sung et *** used to correlate the solubility data of Fe(acac)3 and Ni(acac)*** equations obtained can be used to predict the solubility of the same system in the experimental range.

关键词： Iron(III)acetylacetonate Nickel(II)acetylacetonate Supercritical carbon dioxide Solubility measurement Correlation model Phase equilibrium

Catalytic recycling of polyesters via a binuclear catalyst

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Science China Chemistry 2024年第2期67卷 426-427页

作者： Bo sun Ding Ma Beijing National Laboratory for Molecular Science New Cornerstone Science LaboratoryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

Plastics play a crucial role in modern society life. While the increasing use of plastics and rapid accumulation of plastic waste in nature environment have caused severe environmental crisis and the waste of carbon resources. Catalytic upcycling is a promising approach to transform plastic waste into high value-added chemicals to achieve a sustainable circular economy.

关键词： Catalytic polyester catalyst

Microstructure,mechanical and fracture properties of friction stir welded 2195 Al-Li alloy joints

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Chinese Journal of Aeronautics 2024年第1期37卷 345-361页

作者： Guangda sun Weizhao sun Li ZHOU Sanfeng LUO Zili ZHANG Debo LIU Huiqiang WU State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology(Weihai)Weihai 264209China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

The 8 mm-thick 2195 Al-Li alloy joints were achieved by Friction Stir Welding(FSW).The microstructural evolution,temperature-dependent mechanical properties,and fracture properties were *** T1,δ’/β’and θ’precipitates were observed in the Base Metal(BM)and the Heat Affected Zone(HAZ).Most of the precipitates,except for re-precipitated δ’/β’phases,were dissolved in the Nugget Zone(NZ).The tensile specimens that failed at cryogenic temperatures(-196℃)had the maximum Ultimate Tensile Strength(UTS),and the fracture surface showed the inter-granular fracture *** to those at room temperature(25℃),the decreasing tensile properties at high temperature(180℃)were related to microstructure and strain hardening *** NZ presented the optimal fracture toughness,and the Crack Tip Opening Displacement(CTOD)was mutually dominated by microhardness and grain *** on Fatigue Crack Growth(FCG)rates indicates that the Thermal-Mechanically Affected Zone(TMAZ)exhibited the most superior fatigue resistance performance at stress intensity range below17 MPa.m1/2due to compressive residual stress and the crack closure *** fatigue fracture surfaces reveal that the crack propagation zone was characterized by the striations and secondary ***,inter-granular fracture behavior was responsible for the fastest FCG rates in the NZ.

关键词： Aluminum alloys Friction stir welding Microstructural evolution Mechanical properties Fracture mechanism

High leaf area index expands the contrasting effect of climate warming on Western Siberia taiga forests activity before and after 2000

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Journal of Geographical Sciences 2024年第1期34卷 131-145页

作者： sun Han WANG Xiangping State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing 100083China School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China

The taiga vegetation in Western Siberia has been seriously threatened by climate warming in recent ***,how vegetation in different growing states and climate conditions responds to climate changes differently is still *** we explore the vegetation activity trends in Western Siberia taiga forests using the annual rate of change in leaf area index(LAI)during 1982–2018 so as to answer two questions:(1)how did climate warming affect taiga vegetation activity in the recent last decades?(2)Did the growing state of taiga forest affect its response to climate warming?Our results revealed that climate warming promoted taiga vegetation activity in Western Siberia before ***,continuous warming caused excessive evapotranspiration and led to decreased vegetation activity after ***,the intensity of vegetation growth response to warming was positively related to canopy height and LAI,indicating that both the positive and negative effects of warming were more significant in taiga forests in better growing *** these forests generally have higher productivity and play more important roles in ecosystem functioning(e.g.,carbon sink and biodiversity conservation),our results highlight their vulnerability to future climate change that need more research attention.

关键词： climate warming taiga forest leaf area index(LAI) vegetation activity Western Siberia

Passivity-Based Stabilization for Switched Stochastic Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1307-1309页

作者： Yaowei sun Jun Zhao School of Automation Zhengzhou University of AeronauticsZhengzhou 450046 Henan Key Laboratory of General Aviation Technology Zhengzhou University of AeronauticsZhengzhou 450046China College of Information Science and Engineering Northeastern UniversityShenyang 110819China

Dear Editor,This letter addresses the passivity-based mean square exponential stabilization problem for switched stochastic nonlinear systems.A concept of generalized small-time norm-observability is presented and an appropriate test condition is also *** pre-given passivity rate and average dwell time,a set of feedback controllers is designed by use of the passivity property.

关键词： property letter stabilization

Approaching the commercial threshold of solar water splitting toward hydrogen byⅢ-nitrides nanowires

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Frontiers in Energy 2024年第1期18卷 122-124页

作者： Baowen ZHOU Shuhui sun Key Laboratory for Power Machinery and Engineering of the Ministry of Education School of Mechanical EngineeringShanghai Jiao Tong UniveristyShanghai 200240China Institut National de la Recherche Scientifique(INRS)-CenterÉnergie Matériaux Télécommunications VarennesQuebec J3X 1P7Canada

In a recent article in Nature,Mi and coworkers from the University of Michigan reported a solar-to-hydrogen(STH)efficiency of>9%in converting water into hydrogen and oxygen[1],which represents an important breakthrough in this field due to the benchmarking leap in STH efficiency of photocatalytic overall water splitting under natural sunlight.

关键词： breakthrough splitting Michigan